The purpose of this research project is to develop a porous ceramic-metal composite material suitable for use in structural prosthetic devices. The desired composite would consist of metallic filaments dispersed in a porous ceramic matrix. The pore structure is being designed to allow maximum bone ingrowth for attachment purposes, while maintaining the necessary strength required for structural applications. During the past year, fabrication methods have been developed to obtain porosity in ceramic composites. This was done by hot pressing or sintering the ceramic with polyester fibers in it. The fibers were then burned out leaving the correct amount and size of porosity. Metallic fibers were added to increase resistance to fracture. A seven fold increase was obtained. Problems of interaction between porosity and large quantities of metal fibers were encountered. This is being over come by making the center core of the prosthetic devices solid ceramic with metal fibers and the outer part porous ceramic. These materials are being implanted in dogs at the present. Phosphate bonded aluminum oxide was the first implant but now pure aluminum oxide and hydroxyapatite are being implanted in the rear legs of dogs. This year large sections of bone will be replaced with these laboratory made implants. Fiber filled polymer composites are also being implanted in the mouth area of dogs.